Didn't check the validation

Didn't check the validation but could see there was a red cross in html validator for FF.

The footer issue you describe does not present itself. it's seems to behave!

However you do have issues your left and right columns seem set to proscribed uses i.e they have set widths to suggest narrow sidebar and wider content column you are in fact using these in a reversed manner thus your content is trying to fit in a narrow width and as such the images of a wider fixed width are overflowing the parent.

One thing to do is contain those floated columns the parent needs 'overflow:hidden' to ensure it wraps those columns completely the footer then doesn't really need clear:both not that it hurts to leave it there.